This invention relates to exercise devices for rotating a human user in oscillation and into inverted posture. This type of device is known and is described in U.S. Pat. No. 3,707,285 (Martin), U.S. Pat. No. 3,716,231 (Martin, U.S. Pat. No. 4,232,662 (Barber) and U.S. Pat. Nos. Des. 269,701 and 4,410,176. Ankle holding devices are described in U.S. Pat. No. 3,380,447 and U.S. Pat. Nos. Des. 267,343 and 4,371,494.
The currently known tilt bed exercise devices represent a rather delicately balanced compromise between stability and manufacturing cost, while trying to achieve a degree of portability. The Martin U.S. Pat. No. 3,707,285 shows a simple structure which is very stable in its floor-to-ceiling mounting, and which has only one pivot at each side of the device. Similarly, the device in U.S. Pat. No. Des. 269,701 is also simple and very stable as a floor supported unit, with also only a single pivot at each side. Other products currently available are typified by the Barber U.S. Pat. No. 4,232,662 in which more than one pivot is provided on each side in order to create a folding base which is more portable.